Shi'ite rebels in Yemen have signed a security deal that stipulates disarmament and withdrawal from areas they have seized in recent months.

The agreement was signed one day after the rebels, known as Houthies, overran much of the capital, Sana'a. The takeover effectively made the Houthies the main power brokers in Yemen, a U.S.-allied country whose political, tribal and sectarian turmoil poses risks to the world's top oil exporter, Saudi Arabia, next door.

The deal is part of a comprehensive agreement brokered by the United Nations and includes rivals such as the Muslim Brotherhood-linked Islah party.

The U.S. State Department Saturday condemned the ongoing violence in Yemen and voiced support for President Abd Rabbo Mansour Hadi as he tries to implement the Peace and National Partnership Agreement. The United States called on all parties to implement all aspects of the peace agreement, in particular the turning over of all medium and heavy weapons to the State.

The State Department said the United States is stepping up efforts to work with the international community to pursue sanctions against individuals who are threatening Yemen’s peace, stability, and security, if they do not immediately stop such activities.

Against the backdrop of the fragmented political, tribal and sectarian scene, any escalation of the fighting could also allow an array of other factions, including southern separatists, former leader Ali Abdullah Saleh and even al-Qaida to take advantage.

President Abd-Rabbu Mansour Hadi has said Yemen may be heading for civil war.

Suspected al-Qaida militants attacked a military vehicle in the southern province of Shabwa on Saturday, killing two soldiers and wounding five, a local official told Reuters.

The army launched a campaign earlier this year to flush out al-Qaida in the Arabian Peninsula (AQAP) militants from their strongholds in the provinces of Shabwa and Abyan.